RESUMEN
Folic acid insufficiency is an important risk factor for congenital neural tube defects. Despite recommendations and national campaigns, the proportion of women taking folic acid in the peri-conceptional period remains insufficient worldwide. We describe in this study the proportion of peri-conceptional folic acid supplementation use and its determinants among a population of hospital workers during the course of a prevention campaign. We performed a single-center cross sectional study in a university hospital in France. Data were collected during 2 months in 2019 by an online questionnaire sent to all professionals. We collected information about folic acid supplementation use, its modalities (form, period, frequency and dosage) and reason for initiating or not supplementation. Response rate was 11.4 % (n = 1,075/9,447). Among the 748 women who reported at least one pregnancy, 72.7 % (95 % CI: 69.4-76.0 %) reported taking folic acid during their last pregnancy. Main reason for initiating supplementation was information given by a health professional (87.8 %), especially by gynaecologists-obstetricians. Principal factors associated with folic acid supplementation use were age between 25 and 35 years, high level of education and recent pregnancy. Folic acid supplementation use is still not systematic before and during pregnancy, even among health professionals. There is a case for mandatory folic acid fortification for the French general population.